Harmonic distortion in the modulation source causes bias instability in the resonator fiber optics gyro (RFOG) system. Spurs generated at different harmonics of the fundamental frequency can cause problems. These spurs and harmonics need to be attenuated.
Prior art systems reduced these unwanted spurs by manually adjusting the phase and amplitude of any signal to cancel the spur or by using a method of attenuating these spurs by requiring a filter to be tuned to the fundamental frequency being outputted and then generating a frequency equal to the harmonic or the spur being attenuated.